Finishing machine with reciprocative rotary finishing roll



June 27, 1961 R. w. BERNSTEIN 2,989,823

FINISHING MACHINE WITH RECIPROCATIVE ROTARY FINISHING ROLL Filed March 9, 1959 2 Sheets-Sheet 1 IN VEN TOR. Hus L WBERA/sTE/A/ Ar vAA/EY June 27, 1961 R. w. BERNSTEIN 2,989,823

FINISHING MACHINE WITH RECIPROCATIVE ROTARY FINISHING ROLL 2 Sheets-Sheet 2 Filed March 9, 1959 INVENTOR. RUSSEL L W BERNS TE/N $7012 Arron/v57 United States Patent D 2,989,823 FINISHING MACHINE WITH RECIPROCATIVE ROTARY FINISHING ROLL Russell W. Bernstein, Los Angeles, Calif, assignor to Merit Products, Inc., Los Angeles, Calif, a corporation of California Filed Mar. 9, 1959, Ser. No. 797,994 12 Claims. (Cl. 51-33) This invention relates to machines utilizing drum or rotary brush type abrading or polishing rolls for finishing surface areas of panels, plates, sheets and the like (e.g. drum sanding machines for surface finishing of plywood panels) and has as its general object to provide a machine having an improved arrangement of mechanism mounting a rotating abrading or polishing roll for floating adjustment to the surface of the work, for reciprocative movements of the roll on its longitudinal axis to avoid line-marking of the work parallel to its path of feed, and for high speed rotation of the roll in contact with the work.

A further object is to provide such a machine having an automatic power cut-01f for withdrawing the finishing roll from contact with the work at the point where the rear end of the work arrives directly beneath the roll in the feeding movement of the work.

Other objects and advantages will become apparent in the ensuing specification and appended drawings in which:

FIG. 1 is a perspective view of a finishing machine embodying my invention;

FIG. 2 is a front end elevational view thereof;

FIG. 3 is a detail sectional view illustrating the universal bearing mounts for the drum shaft;

FIG. 4 is a side elevational view of the machine;

FIG. 5 is a plan view of the machine; and

FIG. 6 is a fragmentary sectional view of a modified form of the invention.

Referring now to the drawings in detail, I have shown therein, as an example of one form in which the invention may be embodied, a panel sanding machine utilizing a roll 7 for finishing the fiat surface of a plywood panel or the like 8, the sanding roll being one that may comprise a large number of sheets of abrasive coated fabric, paper, plastic film or the like anchored at their inner edges and projecting radially from a drum 9 having an axle shaft 10 upon which the roll 7 is supported for high speed rotation. The details of construction of the roll 7, forming no part of the present invention, are not disclosed herein but as an example of a sanding roll construction that may be employed, reference may be made to U.S. Letters Patent No. 2,843,980 issued July 22, 1958, in the name of Aleck Block and Russell W. Bernstein.

Shaft 10, at each end, has universally pivotal mounting in self-aligning bearings 11, 11' respectively, the shaft projecting beyond bearing 11 and being provided with a pulley 12 which receives drive through a belt 13 from a drive pulley 14 on the shaft of a drive motor 15. The

drive belt 13 is one having a high degree of lateral flexibility to accommodate its driving travel to reciprocating movement of the pulley 12'and sanding roll 7 along the longitudinal axis of the latterwithoutreducing the effectiveness of drive between the pulleys. 14 and 12. For most satisfactory results, I prefer to use a multiple V- 2 belt and multiple sheave construction in the drive belt 13 and pulleys 12, 14. Such multiple V-belt and sheave construction may be of a well known type.

Merely to illustrate a possible construction to provide the universally pivotal mounting of shaft 10 in bearings;

11, I have shown in FIG. 3 a construction wherein antifriction bearings 16 in which the shaft '10 is mounted for high speed rotation, are provided with outer races of ballform which are socketed, for universally pivotal selfaligning movements, in a segmental-spherical socket 17 defined between a pillow block 18 and a cap 19 of the respective bearing units 11 and 11.

Bearings 11, 11' (FIGS. 4 and 5) are attached to the undersides of a pair of roll support arms 26), 20' which may be of any suitably rigidified or trussed structure as shown in FIG. 4, the roll 7 being suspended beneath the free swinging ends of the arms 20, 20' and the opposite" ends thereof being provided with respective forks 21.

Forks 21 are mounted on respective pairs of upwardly and downwardly projecting trunnions 22 carried by respective forward ends of a pair of lateral arms 23 of a: rocker frame 24 which carries both the sanding roll 7 and" the motor 15. Frame 24 is mounted for tilting move ments on a transverse horizontal axis, by pivotal fulcrum means which may comprise a shaft 25 journalled in bear ings 26 attached to the underside of the forward portion of frame 24, and secured in brackets 27 mounted upon:

the forward side of a fixed stand 28 having legs 29, 29' suitably supported upon and braced to a base 30.

The reciprocating arms 20 may be regarded as consti-- tuting portions of the rocker frame 24, tilting vertically in unison therewith although independently swingable in lateral directions. With the finishing roll 7 and the motor 15 both carried by the frame 24, on opposite sides of thefulcrum shaft 25, they will be counterbalanced against one another and the assembly of frame 24, motor and finishing rolls can be rocked about the fulcrum shaft 25 with the roll 7 being thereby raised away from the work the rear side of stand 28. Actuator 33 may be operated" for tilting the rear end of the frame 24 downwardly to raise the roll 7 from the work at the end of a finishing operation in which the work sheet is fed beneath the roll from end to end. Conversely, the actuator 33 may be operated to lower the roll 7 against the work upon presenting the forward end of the work sheet thereto. The

respective ends of actuator 33 (e.g. of the cylinder and piston rod thereof) are pivotally anchored at 35 and'36 respectively to the pillar 34 and stand 28 respectively While rotating, roll 7 is reciprocated axially by a drive connection to motor 15 comprising a reduction gear unit 37 having an eccentric, pitman, crank or cam 38 driven at reduced speed by the output shaft thereof, a link 39 attached to the eccentric or pitman 38 at one end, and a lever 40 to which the other end of link 39 is pivotally connected as at 41. Lever 40 is shown as constituting an integral extension of an upper bar of reciprocating arm 3 20, extending beyond the pivot 22 thereof. A length adjustment 42 is preferably embodied in the connecting link 39 for setting the roll 7 at a selected median position (between its limits of reciprocating movement) which median position is the one shown in FIG. 5.

Within the horizontal bed 53 I preferably provide a pair of microswitches 44, 44 which are arranged in parallel to close a circuit (not shown) to a control valve for actuator levers thereof. These switches may be normally open switches in series closed by the weight of the work 8 thereon and energizing the actuator control circuit only so long as both switches are closed. The switch 44' functions to start the operation of the motor at the point where the forward end portion of the work 8 has passed beneath the finishing roll 7. The switch 44, previously closed, becomes operative to open the circuit be fore the switch 44- is opened, and at a point prior to engagement of the rear end of the work sheet by roll 7, thus to avoid accidents arising from the rear end of the work panel 8 being forcibly engaged by the rapidly rotating roll 7 and the entire panel kicked forwardly on the table 32 at the point of separation between the work and the roll 7.

Operation In order to operate the machine it is only necessary to close a master switch to energize the motor circuit and to then rest the forward end of the work panel 8 upon the work table 32 and move the forward end up to the roll 7. Upon contacting the switch 44, the forward end of the work panel 8 will actuate the same to effect the lowering of the roll 7 to working position. The rotating periphery of the roll 7 will descend against the work 8 when the forward end portion of the work is beneath the roll 7. The finishing operation will then commence at the proper point in the forward movement of the panel to effect uniform finishing operation on the surface of the panel at the forward end thereof. The contact of the roll 7 with the panel will then automatically feed the panel forwardly, a slight restraining force being applied to the rear end of the panel by the operator to control the rate of feed.

The operation of motor 15 will simultaneously rotate the roll 7, through drive belt 13 while operating the eccentric 38 at a relatively low rate of speed, transmitting, through lever 40 to the roll 7, a lateral reciprocative swinging movement which causes the roll 7 to reciprocate along its axis. Thus the contact of the roll with the work panel 8 will constantly shift laterally to avoid marking the panel with striations extending parallel to the longitudinal axis of the panel. The result is a uniformly smooth finish, devoid of any visible sanding marks or brush marks.

The spacing between pivots 22 and the centers of bearings 11, 11 is the same at both ends of the roll 7 and consequently a parallelogram arrangement is provided wherein, as the arms 20, 20 swing laterally about their pivots 22, the axis of the shaft 10 of roll 7 will remain parallel to a line extending between the pivots 22. During the axial reciprocation of the roll 7, the bearings 16 will have universal pivotal movements within their sockets 17.

FIG. 6 shows how the elevation and lowering of the roll 7 at the beginning and end of a pass of the work sheet below the roll can be provided for by additional actuators 45 (preferably pneumatic) one at each end of the roll, responding to control by the switches 44 and 44'. The upper ends of actuators 45 may be attached rigidly to respective arms 20, and bearings 11, 11' may be carried by heads 46 on the lower ends of the respective piston rods of the actuators. This construction includes all the features shown in FIGS. 1-5, the tilting of rocker frame 23 by actuator 33 being utilized only to adjust the position of roll 7 to varying work thicknesses. The arrangement is an improved one in that it avoids the heavy 4 shocks resulting from the inertia of frame 23 in being abruptly rocked to raise or lower roll several inches for the purpose of applying it to or withdrawing it from the work, which occur in the operation of the machine as shown in FIGS. 1-5.

It may be noted that FIG. 1 is slightly modified, with respect to FIGS. 2-5 in that drive motor 15 and drive 1214 are shown at the right side of the machine as it is faced by the operator, whereas in FIGS. 2-5 these parts are located at the left side of the machine. Either arrangement may be used.

I claim:

1. In a machine for surface finishing panels, sheets and the like: a rocker frame; means supporting said frame for rocking movements on a horizontal transverse axis intermediate its end; a pair of roll support arms pivoted at their rear ends to the forward end of said frame on laterally spaced vertical pivots for lateral swinging movements; a shaft for mounting a finishing roll; bearing means mounting said finishing roll shaft to the forward ends of said support arms for high speed rotation of said shaft upon its own axis and accommodating axial reciprocation of said shaft with reference to the work supporting surface in response to lateral swinging movements of said roll support arms; means carried by said rocker frame for transmitting high speed rotation to said roll shaft; and means carried by said rocker frame for transmitting lateral swinging movements to at least one of said arms and thus reciprocating said roll transversely of the work while being rotated thereagainst; the rocking movementof said rocker frame functioning to move said roll vertically to present said roll to the work and to withdraw it therefrom.

2. A machine as defined in claim 1, including a motor carried by the rear end portion of said rocker frame and in substantially counterbalancing relation to the roll shaft and finishing roll across said transverse rocker axis, said motor being connected for simultaneously driving said high speed rotation transmitting means and reciprocating movement transmitting means.

3. In a machine for surface finishing panels, sheets and the like: a rocker frame, means supporting said frame for rocking movements on a horizontal axis intermediate its ends; a pair of roll support arms pivoted at their rear ends to the forward end of said frame on laterally spaced vertical pivots for lateral swinging movements; a finishing roll shaft; self-aligning hearings in which said shaft is mounted for work-engaging rotation of a finishing roll mounted on said shaft, said bearings also providing selfaligning support of the respective ends of said shaft on the forward ends of said support arms whereby said shaft may be reciprocated axially by said lateral swinging movements of the support arms; means carried by said rocker frame for rotating said roll; and means carried by said rocker frame for swinging said arms and thus reciprocating said roll transversely of the work while being thus rotated, the rocking movements of said rocker frame functioning to move said roll vertically to present said roll to the work and to withdraw it therefrom.

4. In a machine for surface finishing panels, sheets and the like: means providing a work supporting surface in a substantially horizontal plane upon which a work sheet can be slid with a feeding movement longitudinally there of; a rocker frame; means supporting said rocker frame for rocking movements on a transverse horizontal axis above said work supporting surface; a pair of roll support arms pivoted at their rear ends to the forward end of said rocker frame on laterally spaced vertical pivots for lateral swinging movements; a finishing roll shaft for mounting a finishing roll; hearings in which said shaft is mounted for high speed work engaging rotation of said finishing roll, said bearings also providing vertical-axis pivotal support of the respective ends of said shaft on the forward ends of said support arms whereby said shaft may be reciprocated axially by said lateral swinging movements of the support arms with the various positions of 'its axis. remaining parallel to one another and at right anglesto the longitudinal path of feeding movement of the work; means carried by said rocker frame for transmitting high speed rotation to said roll shaft; and means carried by Said rocker frame for transmitting lateral swinging movements to one of said support arms for reciprocating the finishing roll transversely of the work while being thus rotated, the rocking movements of said rockerv frame functioning to move said finishin roll vertically to present the same to the work and to withdraw the same therefrom.

5. A machine as defined in claim 4, including power operated means for vertically rocking said rocker frame to present the finishing roll to the work and withdraw it therefrom; and means in said work supporting surface engaged by the work during feeding movement thereof toward the rear end of the machine, to initiate the rotation of the finishing roll and simultaneously move it toward the work when engaged by the forward end of the work and for arresting the rotation of the finishing roll and simultaneously moving it away from the work when disengaged by the rear end of the work sheet.

6. A machine as defined in claim 4, including a motor mounted on the rear end of said rocker frame in opposed, substantially counterbalanced relation to the finishing roll across said transverse rocker axis, said motor having at one end a driving connection to said high speed rotation transmitting means and at its other end a driving connection to said reciprocating movement transmitting means.

7. A machine as defined in claim 4, including a motor mounted on the rear end of said rocker frame in opposed, substantially counterbalanced relation to the finishing roll across said transverse rocker axis, said motor having at one end a driving connection to said high speed rotation transmitting means and at its other end a driving connection to said reciprocating movement transmitting means, the latter comprising a lever rigid-1y attached to one of said support arms and projecting rearwardly across said transverse rocker axis, a reduction gear unit driven by said motor, and an eccentric drive element and reciprocating connecting link between the output side of said reduction gear unit and the rear end of said lever for developing and transmitting said reciprocating movement.

8. A machine as defined in claim 4, including an electric motor mounted upon said rocker frame rearwardly of said transverse rocker axis and having a drive take-01f at both ends thereof, a multiple V-belt drive between one of said take-offs and one end of said roll shaft, said V-belt drive being freely flexible laterally to accommodate lateral swinging movements thereof in unison with the reciprocating movements of said roll shaft; a reduction drive unit driven from the other of said take-offs; and a pitman and connecting link drive transmitting connection between the output of said reduction drive unit and the arm which supports the other end of said roll shaft, for transmitting lateral swinging movements thereto, said lateral swinging movements being transmitted by said last mentioned arm through said bearing means and through said roll shaft to the other support arm, with said support arms and roll shaft maintaining a parallelogram relationship during reciprocation so as to maintain said parallel relationship between the various positions of the roll shaft during reciprocation.

9. In a machine for surface finishing panels of wood and equivalent fiber materials and the like: a rocker frame; means providing a work-supporting surface below said frame; means supporting said frame for rocking movements on a transverse horizontal axis with vertical movements of an end of said frame toward and away from said work supporting surface; a finishing roll shaft; means supporting said shaft on said frame end for high speed rotation on its own axis and for axially reciprocating movements with reference to said work supporting surface; means carried by said rocker framefor rotating said roll shaft; and means carried by said rocker frame for transmitting said axially reciprocating movements to said shaft during high speed rotation thereof; said rocker said high speed rotation transmitting means and said reciprocating movement transmitting means, said motor substantially counter-balancing said roll shaft and a finishing roll mounted thereon; means for rocking said rocker frame vertically to cause a finishing roll mounted on said roll shaft to move into and away from working contact with a work sheet on said work supporting surface; and control switch means in said work supporting surface adapted to be engaged by the work sheet for starting the operation of the finishing roll and causing it to move downwardly into contact with the work sheet when the forward end of the latter engages said control switch, and for arresting the rotation of the finishing roll and causing it to elevate away from the work sheet when the rear end of the latter passes over said control switch.

10. In a machine for surface finishing panels, sheets and the like: a rocker frame; means supporting said frame for rocking movements on a horizontal transverse axis intermediate its ends; a pair of roll support arms pivoted at their rear ends to the forward portion of said frame on laterally spaced vertical pivots for lateral swinging movements; a shaft for mounting a finishing roll; bearing means mounting said finishing roll shaft to the forward ends of said support arms for high speed rot-ation of said shaft upon its own axis and accommodating axial reciprocation of said shaft with reference to the work supporting surface in response to lateral swinging movements of said roll support arms; means carried by said frame for transmitting high speed rotation to said roll shaft; and means carried by said frame for transmitting lateral swinging movements to at least one of said arms and thus reciprocating said roll transversely of the work While being rotated thereagainst, with the roll axis remaining parallel to a line extending through said later ally spaced vertical pivots; the rocking movement of said rocker frame functioning to move said roll in and out of contact with the work.

11. In a machine for surface finishing panels, sheets and the like: a fixed stand; a rocker frame; pivotal fulcrum means by which said rocker frame is attached to said stand for rocking movements on a horizontal transverse axis intermediate its ends; a pair of roll support arms pivoted at their rear ends to the forward end of said frame on laterally spaced vertical pivots for lateral swinging movements; a shaft for mounting a finishing roll; bearing means mounting said finishing roll shaft to the forward ends of said support arms for high speed rotation of said shaft upon its own axis and accommodating axial reciprocation of said shaft with reference to the Work supporting surface in response to lateral swinging movements of said roll support arms; means carried by said rocker frame for transmitting high speed rotation to said roll shaft; and means carried by said rocker frame for transmitting lateral swinging movements to at least one of said arms and thus reciprocating said roll transversely of the work while being rotated thereagainst; the rocking movement of said rocker frame functioning to vertically adjust said roll with respect to the work.

12. In a machine for surface finishing panels, sheets and the like: a fixed stand; a frame; means mounting said frame on said stand for vertical adjustment of the frame with reference to the stand; a pair of roll support arms pivoted at their rear ends to said frame on laterally spaced vertical pivots for lateral swinging movements; a shaft for mounting a finishing roll; bearing means mount- 7 ing said finishing roll shaft to the forward ends of said support arms for high speed rotation of said shaft upon its own axis and accommodating axial reciprocation of said shaft with reference to the work supporting surface in response to lateral swinging movements of said roll support arms; means carried by said frame for transmitting high speed rotation to said roll shaft; and means carried by said frame for transmitting lateral swinging movements to at least one of said arms and thus reciprocating said roll transversely of the work while being rotated thereagainst; and means for effecting vertical adiustments of said frame'such as to vertically'adiust sa1d roll with respect to the work.

References Cited in the file of this patent UNITED STATES PATENTS 

